Simulation of non-radiative energy transfer in photosynthetic systems using a quantum computer

Photosynthesis is an important and complex physical process in nature, whose comprehensive understanding would have many relevant industrial applications, for instance in the field of energy production. In this paper we propose a quantum algorithm for the simulation of the excitonic transport of energy, occurring in the first stage of the process of photosynthesis. The algorithm takes in account the quantum and environmental effects (pure-dephasing), influencing the quantum transport. We performed quantum simulations of such phenomena, for a proof of concept scenario, in an actual quantum computer the IBM Q, of 5 qubits. We validate the results with the Haken-Str\"obl model and discuss the influence of environmental parameters on the efficiency of the energy transport.POCI-01-0145-FEDER-03094

Planting time for maximization of yield of vinegar plant calyx (Hibiscus sabdariffa L.)

Objetivou-se avaliar a produtividade de cálices de Hibiscus sabdariffa L., planta medicinal, em quatro épocas de plantio em Lavras M.G. Os tratamentos foram quatro épocas de plantio (18 de outubro; 15 de novembro; 18 de dezembro de 2001 e 15 de janeiro de 2002) e realizada uma colheita quando praticamente não existiam cálices em desenvolvimento, quase no final do ciclo da planta. Foram considerados os números de cálices por planta, as fitomassas frescas e secas dos cálices e a qualidade. Concluiu-se que a época de plantio influenciou o rendimento por planta e as fitomassas frescas e secas dos cálices, diferindo entre si pelo teste de Tukey a 5%. No plantio de outubro, houve maior rendimento (2.522 kg/ha), com produção de 5,24 vezes a mais em relação ao plantio do mês de janeiro (481 kg/ha). Os plantios nos meses de novembro e dezembro tiveram produções de 1.695 e 1.093 kg.ha-1 de cálices secos, respectivamente, e em relação ao mês de janeiro, a produção foi 3,52 e 2,27 vezes a mais.Deve-se realizar a colheita assim que os cálices estiverem maduros, a fim de preservar a qualidade

Análise Experimental da conversão RGB/YCbCr e codificação Run-length para compressão de imagens em Sistemas de Tempo Real Baseados em VANTs / Experimental Analysis of RGB/YCbCr conversion and Run-length encoding for image compression in UAV-based Real-Time Systems

Atualmente muitas aplicações que fazem uso de  VANT’s  capturam imagens RGB e as enviam para uma base em terra, em tempo real. O tamanho da imagem transferida é fundamental no atendimento dos requisitos temporais da aplicação Run-length (RLE) e´ uma técnica de compressão de dados adequada para longas sequências de repetições. Foi realizada a conversão RGB/YCbCr e executado o algoritmo de compactação RLE em cada um desses dois espaços de cores.  Os resultados obtidos neste estudo experimental, indicam que a técnica run-length, aplicada ao sistema de cores YCbCr, apresenta vantagens em relação ao RGB, tanto em tempo de processamento quanto em relação as taxas de redução

Estresse no trabalho e hipertensão arterial em mulheres no Estudo Pró-Saúde: Estudo Pró-Saúde (Pro-Health Study)

Con el objetivo de analizar la asociación entre estrés en el trabajo e hipertensión arterial en la población femenina, fue realizado estudio transversal con 1.819 mujeres participantes del Estudio Pro-Salud en Rio de Janeiro, Sureste de Brasil, entre 1999 y 2001. Fue utilizada la versión brasilera de la escala reducida de estrés en el trabajo (modelo demanda-control). La prevalencia global de hipertensión arterial conferida (>;140/90 mmHg y/o uso de medicamento anti-hipertensivo) fue de 24%. Comparadas con participantes con trabajo clasificado como de baja exigencia, las tasas ajustadas de alta exigencia, pasivos y activos, fueron, respectivamente, de 0,93 (IC 95%: 0,72;1,20), 1,06 (IC 95%: 0,86;1,32) y 1,14 (IC 95%: 0,88;1,47). Se sugiere la realización de análisis longitudinales para elucidar el papel de estas características psicosociales del ambiente de trabajo en la determinación de la hipertensión arterial.Com o objetivo de analisar a associação entre estresse no trabalho e hipertensão arterial na população feminina, foi realizado estudo transversal com 1.819 mulheres participantes do Estudo Pró-Saúde no Rio de Janeiro, RJ, entre 1999 e 2001. Foi utilizada a versão brasileira da escala reduzida de estresse no trabalho (modelo demanda-controle). A prevalência global de hipertensão arterial aferida (>;140/90 mmHg e/ou uso de medicação anti-hipertensiva) foi de 24%. Comparadas com participantes com trabalho classificado como de baixa exigência, as razões ajustadas de prevalências de hipertensão arterial de mulheres em trabalhos de alta exigência, passivos e ativos, foram, respectivamente, de 0,93 (IC 95%: 0,72;1,20), 1,06 (IC 95%: 0,86;1,32) e 1,14 (IC 95%: 0,88;1,47). Sugere-se a realização de análises longitudinais para elucidar o papel dessas características psicossociais do ambiente de trabalho na determinação da hipertensão arterial.This study aimed to analyze the association between job strain and hypertension in the female population. A cross-sectional study was performed with 1,819 women who participated in the Estudo Pró-Saúde (Pro-Health Study), in the city of Rio de Janeiro, Southeastern Brazil, between 1999 and 2001. The Brazilian version of the short version of the Job Stress Scale (demand-control model) was used. Overall prevalence of measured hypertension (>;140/90 mmHg and/or antihypertensive drug use) was 24%. Compared to participants with jobs classified as low strain, adjusted prevalence ratios for hypertension in women who performed passive and active high-strain jobs were, respectively, 0.93 (95% CI: 0.72;1.20), 1.06 (95% CI: 0.86;1.32) and 1.14 (95% CI: 0.88;1.47). Longitudinal analyses should be performed to clarify the role of these work environment psychosocial characteristics as a determinant of hypertension

Self-assembled films of dendrimers and metallophthalocyanines as FET-based glucose biosensors

Separative extended gate field effect transistor (SEGFET) type devices have been used as an ion sensor or biosensor as an alternative to traditional ion sensitive field effect transistors (ISFETs) due to their robustness, ease of fabrication, low cost and possibility of FET isolation from the chemical environment. The layer-by-layer technique allows the combination of different materials with suitable properties for enzyme immobilization on simple platforms such as the extended gate of SEGFET devices enabling the fabrication of biosensors. Here, glucose biosensors based on dendrimers and metallophthalocyanines (MPcs) in the form of layer-by-layer (LbL) films, assembled on indium tin oxide (ITO) as separative extended gate material, has been produced. NH3+ groups in the dendrimer allow electrostatic interactions or covalent bonds with the enzyme (glucose oxidase). Relevant parameters such as optimum pH, buffer concentration and presence of serum bovine albumin (BSA) in the immobilization process were analyzed. The relationship between the output voltage and glucose concentration shows that upon detection of a specific analyte, the sub-products of the enzymatic reaction change the pH locally, affecting the output signal of the FET transducer. In addition, dendritic layers offer a nanoporous environment, which may be permeable to H+ ions, improving the sensibility as modified electrodes for glucose biosensing.CAPESCNPqFAPESPFAPEMI

Short version of the "job stress scale": a Portuguese-language adaptation

OBJECTIVE: To describe the adaptation to Portuguese of the short version of the "job stress scale", originally in English. METHODS: We evaluate six aspects of equivalence between the original scale and the Portuguese version: conceptual, semantic, operational, item, measurement, and functional equivalences. A reliability test-retest study was conducted with 94 selected subjects. RESULTS: Reproducibility (interclass correlation coefficients) for the 'demand', 'control', and 'social support' dimensions of the scale was estimated at 0.88, 0.87, and 0.85, respectively. Internal consistency (Cronbach's alpha) estimates for these same dimensions were 0.79, 0.67, and 0.85, respectively. CONCLUSIONS: Our results suggest that the adaptation of the scale was successful, and indicate that its use in the sociocultural context of the studied population (Pró-Saúde survey) is appropriate.OBJETIVO: Descrever o processo de adaptação, para o português, da versão resumida da "job stress scale", originalmente elaborada em inglês. MÉTODOS: Foram avaliados seis aspectos de equivalência entre a escala original e a versão para o português: as equivalências conceitual, semântica, operacional, de itens, de medidas e funcional. Tomou-se por base um estudo de confiabilidade teste-reteste com 94 indivíduos selecionados. RESULTADOS: O estudo de confiabilidade teste-reteste entre 94 indivíduos permitiu estimativas de reprodutibilidade (coeficientes de correlação intraclasse) para as dimensões de "demanda", "controle" e "apoio social" da escala de 0,88, 0,87 e 0,85, respectivamente. Para as mesmas dimensões, as estimativas de consistência interna (alpha de Cronbach) foram, respectivamente, 0,79, 0,67 e 0,85. CONCLUSÕES: Os resultados sugerem que o processo de adaptação da escala foi bem sucedido, indicando que seu uso no contexto sociocultural da população de estudo (Estudo Pró-Saúde) é apropriado

Nanostructured polyaniline thin films as pH sensing membranes in FET-based devices

Polyaniline (PANI) has become an important conducting polymer for sensing due to its morphological and electrical properties. However, the processing of polyaniline in the form of nanostructured thin films is often limited by the low solubility of the polymer in water. We synthesized nanostructured polyaniline (N-PANI) aimed at improving its solubility to form layer-by-layer (LbL) thin films in conjunction with poly(vinyl sulfonic acid) (PVS) as counter ion. N-PANI was characterized via spectroscopic measurements and SEM images. After assembled as LbL thin films onto gold (Au) substrates, the PVS/N-PANI were employed as separative extended gate pH sensing membrane in FET-based devices presenting pH sensitivity around 58 mV/pH with small voltage drift. The results suggest that N-PANI can be easily processed to form suitable thin films for pH sensing and can be combined with biomolecules to be applied in FET-based biosensors.CAPESCNPqFAPES

Ion-sensing properties of 1D vanadium pentoxide nanostructures

The application of one-dimensional (1D) V2O5 center dot nH(2)O nanostructures as pH sensing material was evaluated. 1D V2O5 center dot nH(2)O nanostructures were obtained by a hydrothermal method with systematic control of morphology forming different nanostructures: nanoribbons, nanowires and nanorods. Deposited onto Au-covered substrates, 1D V2O5 center dot nH(2)O nanostructures were employed as gate material in pH sensors based on separative extended gate FET as an alternative to provide FET isolation from the chemical environment. 1D V2O5 center dot nH(2)O nanostructures showed pH sensitivity around the expected theoretical value. Due to high pH sensing properties, flexibility and low cost, further applications of 1D V2O5 center dot nH(2)O nanostructures comprise enzyme FET-based biosensors using immobilized enzymes.CAPESCAPESCNPqCNPqFAPESPFAPES

Production and characterization of natural rubber-Ca/P blends for biomedical purposes

This study presents the development of natural rubber-Ca/P blends, as promising candidates for biomedical purposes. The specific objectivewas the incorporation of Ca/P into a natural rubber polymericmatrix. Ca/P crystalline phaseswere synthesized by the sol-gel method and the polymeric matrices were produced using natural rubber extracted from latex of the Hevea brasiliensis. The shape and size of natural rubber particles present in the NR membrane, as well as, the way the Ca/P powder grains aggregate in the polymeric matrix were investigated, giving information about the interactions between the Ca/P and the natural rubber particles. Confocal fluorescence scanning microscopy measurements allowed us to propose a structure where the Ca/P grains are surrounded by natural rubber particles. This structure may mediate Ca2+ release for tissue regeneration. The systeminvestigated may open new horizons for development of a bandage which provides the controlled-release of biomaterials.CNPq (555100/2010-3)CAPES (PNPD/2583/2011)INCT/INEONanoBiome